Firstly, huge thanks to the kind folks at @Pebble for sending me a unit to play with: you guys rock. I can't wait to get my hands the SDK. Also congratulations on pioneering animated GIF based customer support: it works surprisingly well.

As I tweeted earlier today, I managed to get Pebble to work with Spotify on my Nexus 4. I can't guarantee this is going to work for all devices and versions of Android, but I've verified it works on the Nexus 4 and the Galaxy Nexus both running Jelly Bean. I had issues with my Nexus One, but that's still running Gingerbread. If you're running something newer maybe you'll have more luck. So, without further ado, here's the quick guide to getting it working:

Hopefully that works for you. Report success/issues to me @Hexxeh. You might find you have to tweak the settings in Media Button Router so that Spotify is the only app that recieves commands. Strangely enough, I also found that it still worked after I uninstalled Media Button Router, but YMMV.